Presently available treatments for snakebite suffer from a number of disadvantages, all of which are avoided by the present invention.
Prior to the introduction of anti-venoms, the most commonly used treatment for snakebite was incision and suction. Prompt incision-suction can remove lethal amounts of venom, and in some cases where medical treatment is unavailable a sufficient amount of venom may be removed to be lifesaving. However, this method has not always been effective. In severe cases, amputation, including amputation by self-treatment, has been necessary. Tourniquets may be employed, alone or with incision and suction, as a temporary measure by persons who have suffered a snakebite and are remote from convenient medical help.
The presently preferred treatment for snakebit, if medical help is available, is the use of anti-venom. Natural venom contains all the antigens of a given venom and therefore produces the best anti-venoms or anti-serums to the toxins contained in snake venom. The currently available anti-venoms are generally prepared by injecting the venom of a given snake into horses and extracting the anti-venom produced therefrom from the horse serum. However, the use of anti-venoms suffers from a number of serious disadvantages.
Administration of anti-venoms must always be by intravenous drip. Serum sensitivity first has to be assessed by injecting diluted horse serum obtained, for example, from Wyeth Pharmaceutical Company or similar sources or by administering 0.2 ml of undiluted anti-venom subcutaneously. If the snakebite victim exhibits sensitivity, slow administration of anti-venom is necessary, along with concurrent administration of massive dosages of glucocorticoids and large doses of antihistamines such as cyproheptadine, trimeprazine, or methdilazine. Since all of the above-named potent antihistamines also possess significant antiserotonin activity, they may also have to be given intravenously. Ephinephrine may also be required. In other words, the snakebite victim must be hospitalized in order to receive proper treatment. Even with careful medical attention, serum sickness is common after anti-venom administration. Therefore there has been a longstanding need for a less toxic treatment for snakebite.
The ideal anti-snake venom agent would be one which could be administered orally and thus could be taken by the snakebite victim at the time he receives the bite. It would also be highly desirable to provide an agent which could be administered prior to a potential victim's exposure to snakebite and which would protect him from subsequent snakebite. The present invention provides such agents.
The ground roots of the plants Berkheya spekeana and Echinops amplexicaulis, both of the compositae family, have been used as anti-snake venom treatment by a limited number of people living in a part of East Africa who kept the remedy secret. It has not been possible prior to this invention to provide controlled dosages of the active factors in the roots and to eliminate the side effects of the other materials in the roots.